2. Molecular Biology – 2.8 Cell Respiration
Name:
Understandings, Applications and Skills (This is what you maybe assessed on)
Statement
Guidance
2.8.U1
Cell respiration is the controlled release of energy from
organic compounds to produce ATP.
Details of the metabolic pathways of cell
respiration are not needed but the
substrates and final waste products should
be known.
2.8.U2
ATP from cell respiration is immediately available as a
source of energy in the cell.
2.8.U3
Anaerobic cell respiration gives a small yield of ATP from
glucose.
2.8.U4
Aerobic cell respiration requires oxygen and gives a large
yield of ATP from glucose.
2.8.A1
Use of anaerobic cell respiration in yeasts to produce
ethanol and carbon dioxide in baking.
2.8.A2
Lactate production in humans when anaerobic respiration
is used to maximize the power of muscle contractions.
2.8.S1
Analysis of results from experiments involving
measurement of respiration rates in germinating seeds or
invertebrates using a respirometer.
There are many simple respirometers which
could be used. Students are expected to
know that an alkali is used to absorb CO2,
so reductions in volume are due to oxygen
use. Temperature should be kept constant
to avoid volume changes due to
temperature fluctuations.
Recommended resources:
http://bioknowledgy.weebly.com/28-cell-respiration.html
Allott, Andrew. Biology: Course Companion. S.l.: Oxford UP, 2014. Print.
2.8.U1 Cell respiration is the controlled release of energy from organic compounds to produce ATP.
1. Define cell respiration
2. Cell respiration is an example of a metabolic process. State the type of molecules that control the
process of respiration.
3. Explain why cell respiration must happen within every living cell.
4. Identify two organic molecules, other than glucose, which could be used for respiration.
5. Identify the two components of the cell in which respiration takes place.
2.8.U2 ATP from cell respiration is immediately available as a source of energy in the cell.
6. Draw and annotate a molecule of ATP to show how it stores and releases energy.
http://bioknowledgy.weebly.com/
(Chris Paine)
7. List the three main cellular process that use ATP as a source of energy.
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8. Distinguish between the terms aerobic and anaerobic.
2.8.U4 Aerobic cell respiration requires oxygen and gives a large yield of ATP from glucose.
9. Label the diagram of aerobic cell respiration below.
2.8.U3 Anaerobic cell respiration gives a small yield of ATP from glucose.
10. Label the diagram of anaerobic cell respiration below.
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(Chris Paine)
11. Complete the table below to compare and contrast aerobic and anaerobic respiration.
Aerobic
Anaerobic
Glucose (and other hexose sugars) used in both types of respiration
Lipids and amino acids (if in excess) can
also be used
Oxygen in
2 ATP produced
Pyruvate is an intermediate compound in both types of respiration
Yeast
Animals
Carbon dioxide produced
Water produced
2.8.A1 Use of anaerobic cell respiration in yeasts to produce ethanol and carbon dioxide in baking.
12. Describe how and why yeast is used in bread making.
http://bioknowledgy.weebly.com/
(Chris Paine)
13. Bioethanol is ethanol produced by living organisms, for use as a renewable energy source. It can be
used as a fuel in vehicles, sometimes in a pure state and sometimes mixed with gasoline (petrol).
Describe how bioethanol can be produced from plant material with reference to the function of yeast in
the process.
2.8.A2 Lactate production in humans when anaerobic respiration is used to maximize the power of muscle
contractions.
14. State three activities that require anaerobic respiration.
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15. Aerobic respiration generates a much greater yield of ATP. Despite this it is still important for humans to
carry out anaerobic respiration. State the main advantages to humans of anaerobic respiration.
16. Explain why anaerobic respiration can only be done for short periods of time.
17. Describe the term ‘oxygen debt’ and explain why it must be repaid after anaerobic respiration has
stopped.
http://bioknowledgy.weebly.com/
(Chris Paine)
2.8.S1 Analysis of results from experiments involving measurement of respiration rates in germinating seeds
or invertebrates using a respirometer. & Nature of Science: Assessing the ethics of scientific research—the
use of invertebrates in respirometer experiments has ethical implications. (4.5)
Respirometers vary greatly in their design, but all
can be used to calculate the rate of respiration
by measuring the consumption of oxygen. Below
shows the design of a typical respirometer.
18. Explain the function of each of the following
parts of the respirometer.
a. Potassium hydroxide (alkali) solution:
b. Filter paper wicks:
http://www.nuffieldfoundation.org/practical-biology/measuring-rate-metabolism
c. Capillary tube containing coloured oil:
d. Rubber bungs sealing each tube:
e. Syringe:
f.
Metal cage:
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(Chris Paine)
19. The respirometer could function without the presence of tube A. Given that fact explain why the inclusion
of tube A still important to the validity of the results obtained from the respirometer.
20. The respirometer can be used to measure the rate of respiration in a range of experiments.
g. Outline how the respirometer can be used to measure the impact of temperature upon respiration.
h. The respirometer above can also be used to measure the respiration rate in small invertebrates.
Describe the ethical and environment concerns that must be addressed before the respirometer can
be used for animal experimentation.
21. In the absence of equipment you can use the follow the worksheet (Q1-10) and complete the virtual lab.
 http://biologycorner.com/worksheets/cellular_respiration_AP_Lab5_virtual.html
Citations:
Allott, Andrew. Biology: Course Companion. S.l.: Oxford UP, 2014. Print.
Taylor, Stephen. "Essential Biology 03.7 Respiration.docx." Web. 18 Nov. 2014.
<http://www.slideshare.net/gurustip/essential-biology-37-respiration-core>.
http://bioknowledgy.weebly.com/
(Chris Paine)